(FORTUNE Magazine) – Somewhere en route from dirt-poor Mississippi schoolgirl to TV news anchor to talk-show empress to award-winning actress to therapist for an anxious nation, Oprah Winfrey became a businesswoman. It's a title she doesn't like much. "I don't think of myself as a businesswoman," she announces at the beginning of a four-hour sit-down--the first extensive interview she's given to a business publication. "The only time I think about being a businesswoman is now, while I'm talking to you. There's this part of me that's afraid of what will happen if I believe it all."

You'd be hard pressed to find another American chief executive this disarming, this confessional. But it's oh-so-Oprah. Sitting in an overstuffed armchair in her office in Harpo Inc.'s Chicago headquarters, her two cocker spaniels lying at her feet, the chairman swears that if she is a businesswoman, it's in spite of herself. She happily admits that she cannot read a balance sheet. She has no corporate role models. She's kissed Tom Cruise and more than one world leader, but she has never even met Jack Welch or Michael Dell. She's declined invitations from AT&T, Ralph Lauren, and Intel to sit on their corporate boards. "I just say, 'Guys, I don't know what I'd be doing on your board.' " And she's so wary of investing her own money in the stock market that she once hoarded $50 million in cash, calling it her personal "bag-lady fund."

Winfrey--we'll call her Oprah, just because everybody else does--is kidding herself. Despite her protestations, she is at the helm of a mighty successful business. At its foundation is The Oprah Winfrey Show with its 22 million U.S. viewers, but she's been branching out into movie production, cable TV, magazines, and the Internet. She's at the peak of her power--and frankly, she's confused. In the fall she told FORTUNE that she was "at a crossroads. Not a crisis, but a juncture." Over the next few months she seemed reinvigorated but was still waffling about where she was headed. Then in mid-March, as this story was going to press, Harpo disclosed that Oprah would quit her show after the 2005-06 season, her 20th year in talk TV. "I like even numbers," says Oprah. And she wants to go out on top.

Take that statement for what it's worth. Oprah has publicly contemplated quitting her show before and is notorious for spur-of-the-moment decisions. But if she does follow through on this plan, the disappointment will surely spread beyond her show's loyal viewers. Walt Disney President Bob Iger, whose ABC network airs her syndicated show in most major markets, says Oprah contributes "tremendous profits" to Disney, thanks to ad sales and the lead-in lift she gives to the network's schedule. In the book-publishing industry, where margins are tight, an Oprah endorsement can make all the difference. Dick Parsons, CEO-designate of AOL Time Warner (which owns Warner Books as well as Time Inc., FORTUNE's publisher), says that the Oprah's Book Club insignia on a novel typically pumps up sales tenfold. No Oprah, no megaphone to trumpet the books.

The Oprah show is clearly the core of her business, contributing the lion's share of revenues--some $300 million last year--to Harpo. It airs in 107 countries and has held its No. 1 spot in U.S. daytime talk for 16 years despite challenges from at least 50 rivals. It's a mass-market megahit that appeals to the middle-aged, middlebrow audience that advertisers such as Procter & Gamble, Sears, and Wal-Mart are eager to reach. But it's hardly her only venture.

Her two-year-old magazine, O, The Oprah Magazine, is the most successful startup ever in the industry. Last year it raked in more than $140 million in revenues. According to her joint-venture partner, Hearst Magazines President Cathleen Black, it is "significantly profitable," a remarkable feat given that successful magazines generally take five years to turn a profit. In an advertising recession so tough that titles such as Mademoiselle and Talk have disappeared, O's ad sales actually rose 43% in the first four issues of the year, compared with the same four last year. The magazine reaches a richer set of fans than those watching the daytime TV show. O readers have an average income of $63,000 and lean towards brands like Lexus, Donna Karan, and Coach. And they seem to love this "personal-growth manual," as Oprah describes the monthly; O has a paid circulation of 2.5 million, more than Martha Stewart Living or Vogue--or this magazine, if you must know.

Her movie production division turns out award-winning television films like Tuesdays With Morrie and brings in about $4 million a year. Her "guru" business last year generated $1.6 million in ticket sales as 8,500 women in four cities paid $185 each to hear Oprah deliver her gospel of self-affirmation on her "Live Your Best Life" tour. She also holds a substantial stake in Oxygen Media, a cable TV company for women, for which she produces and stars in a show called Use Your Life.

Forced by this reporter to listen to this litany of accomplishments, Oprah tucks her loafered feet into the cushion of her big chair and fesses up. "Yeah," she acknowledges, "I guess I am a businesswoman." A businesswoman, however, with a lot of other ideas spinning around her brain.

To understand what makes Oprah Inc. such a powerhouse business, you must first understand the simple message that makes Oprah the new Queen of Soul. (If you don't get this, you're probably a guy, and in that case just sit up and pay attention.) Put simply, says Oprah, "my message is, 'You are responsible for your own life.'" It's as consistent a selling proposition as McDonald's convenience or Wal-Mart's everyday low prices. Here's how it translates into a business model: "We bet on ourselves," says Jeff Jacobs, president of Harpo and Oprah's longtime No. 2. "We are an intellectual property company, and our partners [ABC, Hearst, Oxygen] are distributors. Core content is developed here and has never left our home base."

Controlling the content is an especially interesting challenge for Harpo, since Oprah is not just the chief content creator but the chief content itself. Every single copy of O displays a bold, winning image of Oprah on the cover. The details of her personal life--her triumphs over adversity and abuse, her endless battle against weight gain--have been aired with a just-girls-yacking honesty on her show. "I bring all my stuff with me," she says. And by making herself and her struggles central to her message, she taps deeply into the American psyche and its desire for self-reliance.

Oprah's life is the essence of her brand, and her willingness to open up about it on daytime TV helped win the enduring trust of her audience. Given all that, it's not surprising that Oprah has been very, very reluctant to cede control of her brand. Food marketers, clothing designers, perfume manufacturers, book publishers, and innumerable pie-in-the-sky entrepreneurs have tried to persuade Oprah to license her name for their products. As Oprah's longtime friend Gayle King puts it, "Everybody's thinking, 'I gotta get a piece of that Oprah brand.'" Unlike fellow living brand Martha Stewart, Oprah has steadfastly resisted these entreaties. Early on, Stewart lent her name to Kmart to sell housewares, and that company is now in Chapter 11. Stewart, who looked for fast growth, also gave up control by taking her company public three years ago; the stock once approached $40 but now sells for $19.

For the first 14 years of her company's existence, in contrast, Oprah made just two alliances, and both were absolutely necessary--with TV syndicator King World to distribute her show and with ABC to air her TV movies. In the past few years she has, with trepidation, made deals with Hearst and Oxygen. She has refused to take her company public. Oprah says that selling her name--or any part of her business--is akin to selling herself. "If I lost control of the business," she says, "I'd lose myself--or at least the ability to be myself. Owning myself is a way to be myself."

And being her "authentic self" (in the words of Oprah "life strategist" Dr. Phil) has not always been easy. In her traumatic first major TV job in Baltimore, the station bosses wanted her to change her hair, lips, nose, and just about everything else. Dennis Swanson, who recruited her to Chicago in 1983 and is now president of WNBC-TV in New York, was the first exec who let Oprah be Oprah. He recalls: "I hadn't met her before she came to my office. She desperately wanted to be hired to do the AM Chicago show. She said, 'Do you have any concerns about me?'

"I said, 'No, not that I can think of.'

"'Well, you know I'm black,' she said.

"I told her, 'Yeah, I figured that out.'

"Then she said, 'You know I'm overweight.' I said, 'So am I. I don't want you to change your appearance. If I wanted a glamorous person, I'd have hired someone else.'" Swanson paid her $230,000 a year and ran her show opposite Phil Donahue's, who had dominated TV talk in Chicago for more than a decade. Within a month Oprah was beating Donahue in the ratings.

Dennis Swanson convinced Oprah that she could succeed by being herself; Jeff Jacobs convinced her she could run an empire. Jacobs, 52, is the little-known power behind the media queen's throne. He was a Chicago entertainment lawyer in 1984 when Oprah arrived at his office in flip-flops and a red AM Chicago T-shirt looking for help with a new contract. He quickly convinced her to bet on herself--that is, to establish her own company rather than be talent for hire, as most TV stars are. When they set up Harpo (Oprah spelled backwards) in 1986, she gave Jacobs 5% of the company. Three years later, Jacobs joined as president, and Oprah handed him 5% more. Today Oprah owns a bit more than 90% of Harpo, as the company has moved into the magazine business in which Jacobs has no stake.

They're an odd couple, but the relationship works. Besides acting as Oprah's strategic advisor, Jacobs is her combative dealmaker. He is "a piranha--and that's a good thing for me to have," says Oprah. Says Disney's Iger, who wrangled with Jacobs over movie deal details: "I remember being put off initially, but Jeff Jacobs has one thing in mind: his client. And he serves her very well." Jacobs declined to be photographed for this story, since he views himself as a "behind-the-scenes guy." In that role he is perfectly happy to take on jobs most corporate presidents wouldn't touch, such as serving as Oprah's personal agent, for no fee, when she takes roles in movies and on TV. Thanks to that arrangement, she doesn't give up 25% of her pay to agents and managers, as other stars do. "One of the reasons Oprah is so financially successful," Jacobs boasts, "is that we understand it's not just how much you make but how much you keep."

Still, the tension between the gut-driven chairman and the wily president is palpable. "In 1998 Jeff said to me, 'Let's figure out how we can come up with the next Oprah,'" she recalls. "I said, 'We didn't figure out how to come up with this one!' If we had sat in a room and planned this, we never would have created what we have." She describes her business decisions as "leaps of faith." Grinning, she says, "If I called a strategic-planning meeting, there would be dead silence, and then people would fall out of their chairs laughing." Even when they agree, Jacobs and Oprah speak different languages. Jacobs told Fortune that Harpo's strategy is to "multipurpose our content" in various media. For example, Dr. Phil appears every Tuesday on Oprah, writes a Q&A column in O, and in September will launch his own daily Harpo-backed TV talk show. "Multipurposing the content?" Oprah bristles. "He's never used that term with me."

Oprah embraces management-by-instinct, but the method hasn't always served her well. Over the years unhappy former employees have revealed tidbits about Harpo as a less-than-loving workplace. "An environment of dishonesty and chaos" is how one former publicist described Harpo in a 1994 statement accompanying a suit seeking severance and back salary. (That suit was settled quietly two years later.) Oprah has successfully intercepted revelations by insisting that everyone who works at Harpo sign an unusual lifelong confidentiality agreement. "You wouldn't say it's harsh if you were in the tabloids all the time," Oprah says in her defense.

The confidentiality agreement underscores what is both her business' greatest strength and its potential downfall: Oprah's business is Oprah. If she does something as Oprah the person that undermines the trust her customers have in Oprah the persona, her brand could quickly fizzle. It's a threat that Oprah has under tight control. Elizabeth Coady, a former senior associate producer, quit in 1998 and intended to write a book about her experiences at Harpo. Coady calls Harpo, where she worked for more than four years, a "narcissistic workplace." Of Oprah, Coady says, "Everyone undermines everybody else to get more access to Oprah, and I think she encourages it." But it's unlikely we'll hear more details in a book; an Illinois appeals court upheld the confidentiality agreement Coady had signed.

Harpo won't comment on these suits, but Oprah does acknowledge that in the early days she ran people ragged. She says her wake-up call came one night when an exhausted producer fell asleep inside her garage with her car motor running. Luckily the woman's radio woke her up. But Oprah, who believes in signs from above, realized, "We were like overzealous moms who are proud that they do everything themselves, without any help." So she hired a nanny: She brought on her favorite former boss, a TV station exec named Tim Bennett, as chief operations officer. She gave Bennett the go-ahead to build real corporate departments--accounting, legal, and human resources--to make the place run like a real company. Bennett says that when he arrived in 1994, he requested a meeting with his new boss to discuss the capital plan. "What's a capital plan?" Oprah asked. "It's your equipment," he replied. "I told her I needed 15 minutes. Oprah said, 'I'll give you five.'"

Today Harpo has 221 employees (68% are women), modest turnover (10% to 15% a year), and stability at the top. The average tenure of 16-year-old Harpo's ten most senior execs is ten years. The cavernous Harpo headquarters, housed in a onetime hockey rink reconfigured into a maze of offices and production facilities, has an in-house spa and a gym--where most mornings Oprah can be spotted sweating on the treadmill. Pay and benefits are "exceptional," says Debbie McElroy, a headhunter with the Lucas Group who recently tried to recruit a $100,000-a-year personal accountant for Oprah. "Employees get an average six weeks' vacation their first year at Harpo," McElroy says. Two of her candidates met with Oprah, but the boss wound up hiring a friend of a friend.

That's typical. Everything is personal at Harpo. While Oprah does delegate operational decisions, she is all over her content. Before O gets shipped to the printer, she reads every word and scrutinizes every picture--typically working on the magazine, via her office PC, from 3 P.M. to 8 P.M. Tuesday through Thursday and all day Friday, when she doesn't shoot her show. "She's into every little niggly thing--the commas, the exclamation points," says Gayle King, who, as editor-at-large, is Oprah's eyes and ears at the Manhattan-based magazine.

Sometimes her personal desires clash with business demands. O's table of contents runs on page 2 instead of page 22, unusual in a women's magazine. Advertisers would prefer that readers wade through a bunch of ads as they search for the table of contents, "but Oprah said, 'Let's put the readers first,'" recalls Hearst's Black. And when O launched in the spring of 2000, Oprah wanted it to reach all consumers on the same day--just as The Oprah Winfrey Show reaches the vast majority of households at 4 p.m. weekdays. Black recalls: "I had to explain to her, 'Oprah, it's still rolled out by trucks, which go to 185,000 newsstands." Oprah's take on magazine distribution: "It's antiquated."

The success of the magazine stunned Oprah. "I'm most proud of the magazine," she says, "because I didn't know what I was doing." But that's disingenuous. The magazine reflects Oprah's gift for balancing preachiness--her desire "to be a catalyst for transformation in people's lives"--with practicality. And she knew that balance would sell, since it's exactly what informs her TV show, where one day she'll interview Jim Carrey and the next she'll tackle the troubles of oppressed women in Afghanistan. With money, too, Oprah has perfected a certain balance. She doesn't track her costs assiduously, but she's aware of them. She recently saw that the show's production costs had ballooned to $50 million a year--at least twice the norm for a daytime talk show. That's okay, she says, but that's also enough: "I did call [Harpo CFO] Doug Pattison to say, 'I think we can keep it at $50 million,'" she says.

She tries to keep all the number stuff away from her creative employees. "The absolute truth is that we do not worry about the numbers," says Dianne Atkinson Hudson, the longtime executive producer of The Oprah Winfrey Show. "Ratings go down when we do an Oprah's Book Club show, but that doesn't matter. We're getting people to read." Kate Forte, president of Harpo Films in Los Angeles, says that Oprah showers kudos on the staff before one of her TV movies airs. But if it wins big ratings or awards (as several, such as Tuesdays With Morrie, have), the boss is mum. Says Forte: "It's her reminder that we shouldn't do anything for the external reward." Disney's Iger says he wishes Harpo would produce more films to broadcast on ABC, but Oprah's high standards and strict rules (she won't make a movie based on a book that she has endorsed, for example) limit Harpo's output to one movie per year. "Just because there's a buyer," says Iger, "doesn't mean she's a seller."

When she does sell, Oprah's idea of due diligence is to ask one key question: Can I trust you? "She's definitely on a different plane," says Nancy Peretsman, the only investment banker Oprah has ever worked with. Peretsman, an EVP at Allen & Co., met Oprah four years ago when she was King World's banker. Oprah then hired Peretsman to negotiate her investment in Oxygen. "It's all about character with Oprah," Peretsman says. "We investment bankers do the same sort of thing--try to figure out what people are made of--but with Oprah, it's like someone is looking into your soul."

It helps to know what Oprah wants to find there. Hearst's Black won the battle for O over suitors such as Conde Nast and AOL Time Warner by vowing that the magazine would reflect Oprah and her values. Black's partner on the pitch, Good Housekeeping editor-in-chief Ellen Levine, reeled Oprah in by telling her that the magazine would translate her message into "the written word." Oprah adds that Levine "never put me on the cover of her magazine without my permission." And don't underestimate one other factor: Hearst guaranteed Oprah total editorial control.

Trust also goes a long way toward explaining her investment in Oxygen Media. When Oprah first met Geraldine Laybourne, the Oxygen co-founder explained that she wanted to create a women's cable network based on intent and service. "Intent and service--that is my motto," Oprah says. "I thought, my God, this is my idea exactly." In fact, Oprah had kicked around the idea of starting the Oprah Winfrey Network (OWN) on cable but had never found the time or the courage to develop it. Enamored of Laybourne's plan, Oprah contributed $20 million plus certain rights to The Oprah Winfrey Show library and received a 25% founder's stake. It seemed like a sweet deal at the time, but the two-year-old network has had trouble getting the right programming and buzz. Asked if she is happy with her Oxygen investment, Oprah pauses--one of the rare moments in six hours of interviews when she's at a loss for words. "Am I happy with it?" she says, bouncing the question back. "It is an investment."

The following morning Oprah calls to say that she woke up at 11:19 P.M., worrying about her answer. "I really don't define my happiness by my business decisions," she says. "Now if you ask me, 'Are you uneasy?' I'll tell you that I'm not uneasy about Oxygen itself." She is confident that the cable startup will survive. That's not the issue. The issue is that she deeply regrets handing over the rights to reruns of The Oprah Winfrey Show. "It's not just a commodity," she says. "It's my soul. It's who I am." She's not being rational here: Any knowledgeable banker would say that old Oprah programs have little monetary value. But Oprah says she feels ethically obliged to have a team review every program--more than 2,000--and inform the guests who appeared on the old shows before reruns begin to pop up on the Oxygen channel beginning in September. "I would rather have put $100 million into Oxygen and kept my shows than put in $20 million and given them away," she says. "I feel I gave myself away too readily." After a pause, she adds, "Every time I talk to you, I feel like I'm in therapy."

Oprah never has been in therapy, and for the most part she seems like someone who would hardly need the help. When I first started researching this story last June, I went to see her inspirational "Live Your Best Life" road show. Oprah stood on stage and declared to 1,700 fans: "I believe I'm just getting started. The TV show is just the foundation.... If you're open to the possibilities, your life gets grander, bigger, bolder!"

But when I visited her in Chicago five days before Sept. 11, she seemed utterly different. She talked about being confused about her business. "Maybe I should be in therapy," she teased. She felt more restless than ever, particularly about her talk show. That very week she had done an hour on girls who don't eat and wished they were Britney Spears, and she thought to herself, "I don't know how I'm going to get through the year." She even said to Fortune, "I'm sick of people sittin' in chairs stating their problems. Then we roll the videotape ... then we have our experts on the topic. I truly don't know what to replace it with. As soon as I do, I'm pullin' those people from their chairs." She added, "I'm in the 'what's next?' phase of my career."

Then came Sept. 11, and Oprah got her groove back. Laura Bush's office called, asking if the First Lady could come on the show to talk about children and terrorism. Oprah followed the Laura Bush program with themes such as "Islam 101," "Is War the Only Answer?" and "What Really Matters Now?" During a conversation in January, she was singing a different tune: "What I'm saying to people--Are you living your best life? Are you living your life with passion?--no longer seems so airy-fairy, so cosmic, so out there." (Of course this does not mean Oprah abandoned her commercial side. Far from it. A few days after we talked, Oprah's TV show guest was Britney Spears. According to the description of the program on Oprah.com, "Britney Spears Performs Live...See her sexier, edgier, new look!")

Asked in January if she intended to renew her contract, which expires in August 2004, Oprah said, "I haven't figured that out yet, but I feel more bodacious in stepping out and telling people what my message is."

As we know, she did renew her contract--until 2006. If she truly quits her show in four years, the question, indeed, is, What's next? In her interviews with Fortune, Oprah talked at length about her desire to do something more with her time and money, something significant. She's still mulling her options, and as uncertain as she is, she vows to continue to have a presence on TV. "She's not going to crawl into a corner," says King World boss Roger King, who guesses she will do network specials a la Barbara Walters. But the bodacious vigor she talked about is already taking her--and Harpo--in new, far-flung directions. In early April she plans to go to South Africa to launch the first international edition of O. Cathie Black and her colleagues at Hearst pitched the idea to Oprah last summer, but she wasn't ready. She changed her mind one night last fall while watching a documentary called Africa on PBS. One scene in a Nairobi beauty parlor showed customers reading Hello! and True Love magazines. Kenya and South Africa are 1,800 miles apart, but Oprah's instincts kicked in. "I thought, 'African women have no business sittin' in a beauty shop reading Hello! and True Love.'"

For the first time ever, she's considering licensing her name. Not Martha Stewart-style to build her company's profits, but Paul Newman-style to raise money for charity. She has talked with Newman about his Newman's Own salad dressings, popcorn, and other high-priced foods; the line has generated $125 million for the actor's causes. "It's a beautiful model," says Oprah, who has donated at least 10% of her annual income to charity, most of it anonymously, throughout her adult life. She's interested in working with a cosmetics company because, as she puts it, "cosmetics is something I know." Still, she's not quite there yet. In late February she met with executives from Estee Lauder, but decided she doesn't want to leap into such a big venture...at least for now.

And then there are other projects, none of which has been disclosed publicly until now. She is building a school for girls in South Africa. During her April trip for O, she plans to meet with government officials and educators to discuss building a dozen or so more schools, and perhaps some medical clinics too. Oprah focuses on three causes: women, children, and education. "When you educate a woman, you set her free," says Oprah, who spent her early years in a house without electricity or running water. "Had I not had books and education in Mississippi, I would have believed that's all there was."

Sometimes the opportunities seem virtually unlimited, and that just stresses her out. "I don't care about being bigger, because I'm already bigger than I ever expected to be," she says. "My constant focus is on being better. Should I be doing multimedia video production? Or seminars on the Internet? How can I do what I'm already doing in a more forceful way?" Her companion and unofficial career coach, Stedman Graham, the owner of a leadership training and development firm in Chicago, constantly nags, "You're not doing everything you can do. You need vision!" Lately he has been prodding her to partner with the United Nations "to distribute her message all over the world." Oprah does not exactly embrace the concept. "Oh, my God," she says, "he told you about that?" She hasn't spoken to anyone at the U.N., she adds, "but now they're going to be calling me."

It's not easy being Oprah. People call. They make demands. They ask hard questions. After our last interview, she calls to tell me that she is never going to do another business story. "But this is just your first," I say. "And it's my last," she replies. "I'm not sure why I did it. I'm uncomfortable talking about money and money issues." She may be uncomfortable talking about it, but when it comes to making it, she sure knows what she's doing. And that's only part of the reason why the "what's next?" phase of her career should be one hell of a show.

FEEDBACK: psellers@fortunemail.com